<template>
    <div>
        <v-header :left-text="`上传${columnName}`"></v-header>

        <div class="upload">
            <div v-if="columnName === '视频'">
                <div class="forPreview_video" v-for="(item, index) in uploadVideoList" :key="index">
                    <video :src="videoSrc"></video>
                    <van-icon name="delete" @click="delBtn(index)" class="delte"/>
                </div>
                <van-uploader v-show="uploadVideoList.length < 2" preview-size="80px" accept="video/*" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
            </div>

            <div v-if="columnName === '文档'">
                <div class="forPreview_doc" v-for="(item, index) in uploadDocList" :key="index">
                    <img src="../../assets/img/resource_doc_b@2x.png" alt="">
                    <span>{{item.name}}</span>
                    <span>{{item.size | formatSize}}</span>
                    <van-icon name="delete" @click="delBtn(index)" class="delte"/>
                </div>
                <van-uploader v-show="uploadDocList.length < 2" preview-size="80px" accept=".doc, .docx, .xml, .xlsx, .pdf" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
            </div>

            <div v-if="columnName === '音频'">
                <div class="forPreview_audio" v-for="(item, index) in uploadAudioList" :key="index">
                    <img src="../../assets/img/resource_audio@2x.png" alt="">
                    <span>{{item.name}}</span>
                    <span>{{item.size | formatSize}}</span>
                    <van-icon name="delete" @click="delBtn(index)" class="delte"/>
                </div>
                <van-uploader v-show="uploadAudioList.length < 2" preview-size="80px" accept="audio/*" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
            </div>

            <div v-if="columnName === '图片'">
                <div class="forPreview_pic" v-for="(item, index) in uploadPicList" :key="index">
                    <img :src="picSrc" alt="">
                    <van-icon name="delete" @click="delBtn(index)" class="delte"/>
                </div>
                <van-uploader v-show="uploadPicList.length < 2" accept="image/*" preview-size="80px" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
            </div>

            <div class="diy-submit">
                <van-button @click="doSubmit($event)">提交</van-button>
            </div>
        </div>
    </div>
</template>








<script>
    import VHeader from '../../common/header'
    import {classifyList, uploadFile, addResources} from '../../http/mock'
    import Toast from 'vant'
    export default {
        name: "uploadFile",
        components: {
            VHeader
        },
        data(){
            return{
                tagList: [],  
                uploadTitle: '',
                currentTag: null,
                tagId: null,
                columnName: localStorage.getItem('columnName'),
                fileIdArr: [],

                uploadVideoList: [],  // 选中的上传视频列表
                videoSrc: '',   // 选中的视频的src，用来显示视频
                uploadDocList: [],  // 选中的上传文档列表
                uploadAudioList: [],  // 选中的上传音频列表
                uploadPicList: [],  // 选中的上传图片列表
                picSrc: '',  // 选中的图片的src，用来显示图片缩略图
            }
        },
        filters: {
            formatSize(val) {  // 格式化文件大小
                if (val > 0) {
                    return (val / 1024 / 1024).toFixed(2) + 'M';
                } else {
                    return '0M';
                }
            },
        },
        methods: {
            // vant上传文件前校验文件事件
            // 文件选中后先提交给后台，后台根据选中的文件，返回数组（这一业务根据后台而定）
            beforeRead(file){
                let formData = new FormData();  // 为上传文件定义一个formData对象
                let config = {
                    headers: {
                        'Content-Type': 'multipart/form-data'
                    }
                };
                let uploadUrl = URL.createObjectURL(file);  // 将选中的上传文件转化为二进制文件，显示在页面上
                if(this.columnName === '视频'){
                    this.uploadVideoList.push(file);
                    this.videoSrc = uploadUrl;
                    // 这里使用foreach是为了将选中的多个文件都添加进定义的formdata变量中
                    this.uploadVideoList.forEach(item => {
                        formData.append(item.name, item)
                    })
                }else if(this.columnName === '文档'){
                    this.uploadDocList.push(file);
                    this.uploadDocList.forEach(item => {
                        formData.append(item.name, item)
                    })
                }else if(this.columnName === '音频'){
                    this.uploadAudioList.push(file);
                    this.uploadAudioList.forEach(item => {
                        formData.append(item.name, item)
                    })
                }else if(this.columnName === '图片'){
                    this.uploadPicList.push(file);
                    this.picSrc = uploadUrl;
                    this.uploadPicList.forEach(item => {
                        formData.append(item.name, item)
                    })
                }


                // formData.append(file.name, file);  // 单个文件上传时可以这么写，上面的foreach就可以删掉
                this.$api.post(uploadFile, formData, config).then(res => {
                    this.fileIdArr = res.data.data;   // 把選中的文件傳送給後台
                }).catch(err => {
                    Toast('文件上傳失敗！')
                })
            },
            // 删除待上传的文件
            delBtn(index){
                if(this.columnName === '视频'){
                    // 先判断当前的选中的索引是否是在有效范围中，如果不是则跳出方法 
                    if(isNaN(index) || index >= this.uploadVideoList.length){
                        return false;
                    }
                    let tmp = [];
                    // 将没被选中的上传文件存放进一个临时数组中
                    for(let i = 0; i < this.uploadVideoList.length; i++){
                        if(this.uploadVideoList[i] !== this.uploadVideoList[index]){
                            tmp.push(this.uploadVideoList[i]);
                        }
                    }
                    // 存放当前未被选中的上传文件
                    this.uploadVideoList = tmp;
                }

                if(this.columnName === '文档'){
                    console.log(this.uploadDocList.length)
                    if(isNaN(index) || index >= this.uploadDocList.length){
                        return false;
                    }
                    let tmp = [];
                    for(let i = 0; i < this.uploadDocList.length; i++){
                        if(this.uploadDocList[i] !== this.uploadDocList[index]){
                            tmp.push(this.uploadDocList[i]);
                        }
                    }
                    this.uploadDocList = tmp;
                }

                if(this.columnName === '音频'){
                    if(isNaN(index) || index >= this.uploadAudioList.length){
                        return false;
                    }
                    let tmp = [];
                    for(let i = 0; i < this.uploadAudioList.length; i++){
                        if(this.uploadAudioList[i] !== this.uploadAudioList[index]){
                            tmp.push(this.uploadAudioList[i]);
                        }
                    }
                    this.uploadAudioList = tmp;
                }

                if(this.columnName === '图片'){
                    if(isNaN(index) || index >= this.uploadPicList.length){
                        return false;
                    }
                    console.log('uuu')
                    let tmp = [];
                    for(let i = 0; i < this.uploadPicList.length; i++){
                        if(this.uploadPicList[i] !== this.uploadPicList[index]){
                            tmp.push(this.uploadPicList[i]);
                        }
                    }
                    this.uploadPicList = tmp;
                }
            },
            doSubmit(){
                let params = {
                    classify: this.tagId,        // 针对视频资源时对应的分类id
                    file: this.fileIdArr,   // 选择完文件后，调用uploadFile这个接口，后端返回的数组
                    resourceColumnId: JSON.parse(localStorage.getItem('columnId')),   // 资源栏目id(视频、图片、音频、文档)
                    title: this.uploadTitle    // 上传时填写的标题
                };
                let columnName = localStorage.getItem('columnName')
                this.$api.post(addResources, params).then(res => {
                    if(res.data.code === 1001){
                        if(columnName === '视频'){
                            this.$router.push({name: 'myVideo'});
                        }else {
                            this.$router.push({name: 'myResourceClassify'});
                        }
                    }
                }).catch(err => {
                    console.log(err)
                })
            },
        },
        mounted(){
            this.getClassifyList();
        }
    }
</script>
<style lang="less" scoped>
    .upload{
        padding: 140px 36px 160px 36px;
        box-sizing: border-box;
    }

    .forPreview_video{
        position: relative;
        /*background: rgba(0,0,0,.7);*/
        video{
            width: 95%;
            max-height: 430px;
        }
        .delte{
            position: absolute;
            right: 0;
            bottom: 0;
        }
    }
    .forPreview_doc, .forPreview_audio{
        display: flex;
        margin-bottom: 10px;
        align-items: center;
        img{
            width: 56px;
            height: 56px;
            margin-right: 20px;
        }
        span:nth-of-type(1){
            flex: 1;
        }
        span:nth-of-type(2){
            margin-right: 20px;
        }
    }
    .forPreview_pic{
        display: flex;
        align-items: flex-end;
        img{
            width: 160px;
            height: 160px;
        }
    }

    .diy-detail{
        width: 100%;
        overflow: hidden;
        
        .btn{
            span{
                margin-bottom: 10px;
            }
        }
        .van-cell{
            background-color: #F0F0F0;
            border-radius: 35px;
            font-size: 26px;
            height: 69px;
            line-height: 69px;
            padding: 0 22px;
            color: #999;
        }
        .van-hairline--top-bottom::after, .van-hairline-unset--top-bottom::after {
            border-width: 0;
        }
        p{
            height: 64px;
            line-height: 64px;
            font-size: 32px;
            color: #333;
            position: relative;
            padding-left: 16px;
        }
        p::before{
            position: absolute;
            top: 0;
            left: 0;
            content: '*';
            color: #FF0000;
        }

        span{
            display: inline-block;
            width: 157px;
            background: #F0F0F0;
            border-radius: 35px;
            color: #999;
            font-size: 26px;
            padding: 14px 18px;
            margin-right: 28px;
            text-align: center;
        }
        .active{
            color: #fff;
            background: linear-gradient(to right,#FD5130,#FA6C34);
        }
    }
    .diy-submit {
        position: fixed;
        height: 150px;
        width: 90%;
        bottom: 0;
        background: #fff;

        .van-button {
            width: 100%;
            height: 90px;
            border-radius: 45px;
            font-size: 36px;
            color: #fff;
            background: linear-gradient(to right, #FD5130, #FA6C34);
            top: 50%;
            transform: translate(0, -50%);
        }
        .van-button--default {
            border: none;
        }
    }
</style>